Emergency stop device for an engine supplied by the injection of liquid fuel

ABSTRACT

The supply chamber of the injection pump is provided with a scavenging valve. A supply pump sends fuel through a fuel filter to the supply chamber. A bottle of gas has its mouth sealed by a diaphragm which is pressurized by a percussion mechanism in the case of an accident. The gas is thereby released, flows rapidly through a check-valve into the pipe leading to the supply chamber of the injection pump, sweeps the fuel from this chamber through this scavenging valve and stops the engine.

United States Patent [1 1 Grondel et al.

[451 Sept. 25, 1973 EMERGENCY STOP DEVICE FOR AN ENGINE SUPPLIED BY THEINJECTION OF LIQUID FUEL [75] Inventors: Charles Grondel, La Rochelle;Yves Giraudeau; Jean-Claude Geantet, both of Surgeres, all of France[73] Assignee: Societe Surgerienne De Constructions Mechaniques,Surgeres, France 22 Filed: Feb. 7, 1972 211 App]. No.1 224,093

[30] Foreign Application Priority Data Feb. 11, 1971 France 7104602 [52]US. Cl. 123/198 DB, l23/DIG. 11 [51] Int. Cl. F02b 77/08, F02d 17/04[58] Field of Search 123/198 R, 198 D, 123/198 DB, 198 A, 142, DIG. l1,1, 1 A, 119

[56] References Cited UNITED STATES PATENTS 2,095,349 10/1937 Santschi123/198 DBX 2,551,241 5/1951 Buckland 123/198 DB X 2,737,249 3/19563,371,634 3/1968 3,377,018 4/1968 Nielsen et al. 123/198 D X FOREIGNPATENTS OR APPLlCATlONS 888,949 2/1962 Great Britain 123/198 D 1,224,9003/1971 Great Britain 123/198 D Primary Examiner--Al Lawrence SmithAtt0rneyFlynn & Frishauf [57 ABSTRACT The supply chamber of theinjection pump is provided with a scavenging valve. A supply pump sendsfuel through a fuel filter to the supply chamber. A bottle of gas hasits mouth sealed by a diaphragm which is pressurized by a percussionmechanism in the case of an accident. The gas is thereby released, flowsrapidly through a check-valve into the pipe leading to the supplychamber of the injection pump, sweeps the fuel from this chamber throughthis scavenging valve and stops the engine.

9 Claims, 3 Drawing Figures 1 EMERGENCY STOP DEVICE FOR AN ENGINESUPPLIED BY Til-IE INJECTION OF LIQUID FUEL The invention relates to anemergency stop device for internal combustion engines whose supplysystem comprises a reservoir of liquid fuel a primary pump having asuction pipe connected to the fuel reservoir and a delivery pipe; aninjection pump having a supply chamber where this delivery pipe ends andwhich is connected to the reservoir by means of a spring-biased valve(called a scavenging valve) adapted to be opened when the pressure inthis chamber exceeds a predetermined threshold; and at least oneinjector receiving the fuel from the injection pump to introduce it intothe engine. The invention relates more particularly, but notexclusively, among these stop devices, to those for electrogeneratingsystems (stationary or traction systems for locomotives), marineinstallations (propulsion or electrogenerating units on board ship),industrial units (for drilling rigs, for pumping stations), all types ofunits for which any risk of excessive speed or running away exists.

It is known that, in numerous installations, it is desirable to stopinternal combustion engines as rapidly as possible after the detectionof an accident such as the excessive speed of an electrogeneratingunit.

It has already been proposed (U.S. Pat. No. 2,095,349) to combine withan injection pump a stop device adapted to expel by a gaseous currentthe liquid fuel contained in the supply chamber of this pump. Thischamber, which does not possess a scavenging valve, receives fuel bymeans of an overflow system of which the diverter is connected to thefuel reservoir and it is connected permanently to a source ofpressurized gas, such as an air compressor through a passage on which amechanically actuated valve is mounted. In case of accident, this valveis opened and the gas emerging from the said source penetrates into thesupply chamber and expels the fuel through the diverter of the overflowsystem.

The drawbacks of this stop device are as follows l. the pressure of thesource of gas varies according to the conditions of operation of theengine and can become insufficient to expel the fuel rapidly from thesupply chamber 2. the mechanical actuating valve, if it has defects offluid-tightness, can allow gas to pass towards the supply chamber, onthe normal operation of the engine, which disturbs the injection byintroduction of gas bubbles in the fuel to be injected;

3. the overflow system must have a considerable volume to be able toremove the liquid fuel from the supply chamber in case of suddenstopping and a portion of this fuel risks being jetted to the outsidethrough the aerating device which normally includes such a system at itsupper part;

4. in the case of a sudden stop, the gas under pressure can expel thefuel from the whole of its supply circuit, in particular from theprimary pump, which renders the restoration into starting condition ofthe engine more difficult. I

It is an object of the invention to provide a stop device whichovercomes these drawbacks and especially which is reliable and does notrisk disturbing the normal operation of the engine.

To achieve this purpose, the stop device according to the invention ischaracterized by the fact that it comprises a hollow body which isarranged to receive the neck of a bottle of gas under pressure, normallyobturated by a fluid-tight diaphragm, which body is connected, through afirst check-valve, to a point of the abovesaid delivery pipe situateddownstream of a second check valve and possessing a sudden actionmechanism adapted to pierce the abovesaid diaphragm in case of accidentwhich creates, in the portion of the abovesaid delivery pipe situateddownstream of the abovesaid point and in the supply chamber of theinjection pump, a rapid and momentary current of gas which expels thefuel therefrom towards the reservoir through the scavenging valve andthus causes the stopping of the engine.

It is clear, in fact, that the first check-valve prevents the fuel fromarriving at the hollow bottle-carrying body. On the other hand, itallows to pass the gas coming from the hollow body that the secondcheck-valve obliges to flow towards the supply chamber of the injectionpump.

' In principle, the abovesaid mechanism is a percussion mechanismcomprising a weight movable between an armed position where it is loadedby a spring and retained by a bolt and a released position which it canreach after liberation by its bolt and whereby it causes the piercing ofthe diaphragm.

The invention will, in any case, be better understood with the aid ofthe supplementary description which follows as well as of theaccompanying drawings, which supplement and drawings relate to preferredembodiments, given purely by way of illustrative but nonlimitingexample.

In the drawings:

FIG. 1 shows diagrammatically, in elevation with portions in section theessential elements of a supply system for an internal combustion engineand one embodiment of an emergency stop device constructed according tothe invention;

FIG. 2, shows, in a more detailed manner and in vertical section, anembodiment of the emergency stop device of FIG. 1, and

FIG. 3, lastly, shows with portions in elevation and portions invertical section a modification of the embodiment of the deviceconstructed as in FIG. 2.

Firstly, as regards the internal combustion engine 1, it is constructedso that its supply circuit comprises:

a reservoir for liquid fuel 2;

a primary pump (or supply pump) 3 having a suction pipe 4 connected tothe reservoir 2 and a delivery pipe 5 on which there is generallymounted a fuel filter 6;

an injection pump 7 having a supply chamber 8 wherein the delivery pipe5 ends and which is connected to the reservoir 2 by a channel 9 througha scavenging valve 10;

and at least one injector 11 receiving fuel from the injection pump 7through a channel 12 to introduce it into the engine 1.

Now as regards the stop device 13 of the engine 1, it comprisesessentially, according to the invention, a hollow body 14 arranged toreceive the neck 15 of a bottle of gas under pressure 16, normallyclosed by a sealing diaphragm 17, which body is connected, through achannel 18 provided with a first check-valve 19, to a point 20 of thedelivery pipe 5 situated downstream of the second check-valve 21 andpossesses a sudden action mechanism 22 adapted to pierce the diaphragm17 in case of an accident requiring the stopping of the engine. If theneck 15 possesses a threaded portion, it suffices to provide the hollowbody 14 with a collar 14a threaded internally to receive the neck.

The mechanism 22 is advantageously a percussion mechanism comprising aweight 23 movable between an armed position (position illustrated inFIG. 1 and shown in full lines in FIG. 2), wherein it is loaded by aspring 24 and held by a bolt 25, and a released position (shown in mixedlines in FIG. 2) that it can reach after liberation by its bolt 25 andunder the action of the spring 24 and wherein it causes the piercing ofthe diaphragm 17.

Preferably, the device 13 comprises the non-return valve 21 as soleelement capable of opposing the flow of gas, which enables it tocooperate with a bottle 16 having a volume corresponding to a singlestopping operation. To fill the bottle 16, there is selected a gas inertwith respect to the liquid fuel and inoffensive when it is released intothe atmosphere and, more particularly for reasons of economy, carbonicacid gas or nitrogen. In the case of carbonic acid gas, there may beused a bottle containing a charge of 150 grams under a pressure of 60bars, the device 13 being arranged to ensure the expansion of the gasdown to a pressure of about bars. As shown in FIGS. 2 and 3, it is thenadvantageous to provide, on a same support 26 forming part of the device13, not only the hollow body 14 for the bottle 16 in the position ofuse, but also a tubular element 27 including a collar analogous to thecollar 14a of the said body 14 to receive a reserve bottle 16a. Thesupport 26 may be arranged in the form of a box shielding the essentialelements of the device 13 and provided with openings 28 for the passageof bottles 16, 16a.

In the embodiment of FIG. 2, the hollow body 14 comprises a cylindricalbore 29 in which is guided the mass 23, also cylindrical, and housed, abush 13 serving as a guide for a pin 31. The bush 30 is traversed byholes 32 enabling gas which arrives from the bottle 16 to reach thechannel 18 and it is arranged to prevent this gas from arriving at thebore 29. On the hollow body 14 is adapted a nozzle 33 ensuring theexpansion of the scavenging gas. The hollow body comprises in addition abore 34 which penetrates at a right-angle into the bore 29 and in whichthe bolt 25 is guided. So that the mass 23 of the mechanism 22 can bearmed, it is provided with a handle 35 to which it is connected by a rod36 and which emerges from the box-shaped support 26 so that the positionof this handle indicates in a clearly visible manner whether the stopdevice has or has not already functioned.

To disengage the bolt 25, there is provided, according to the embodimentof FIG. 2, an electromagnetic control constituted by a magnetic coil 37and a plunger 38 such that, when the coil is energized by means ofconductors 39, it effects the withdrawal of the bolt 25, for example bythrusting on a lever 40 of the bell crank type and against the action ofa spring 41.

The modification of FIG. 3 only differs from the embodiment of FIG. 2 bythe substitution of a hydraulic (or pneumatic) control for theelectromagnetic control 37, 38, 39. In this case, the plunger 38 isreplaced by a piston 38a which is adapted to slide in a cylinder 42which can be supplied with fluid under pressure by means of a pipe 43.

Whatever the embodiment adopted, there is obtained a stop device whoseoperation is as follows.

It is first of all necessary to place in position in the hollow body 14a full bottle 16 and to arm the device by pulling the handle 35, fromthe position in mixed lines to the position in full lines in FIG. 2.Moreover, the conductors 39 (FIG. 2) or the pipe 43 (FIG. 3) areconnected to a detector system (not shown) adapted to send a current inthe conductors 39 or a fluid under pressure into the pipe 43 as soon asit detects an accident requiring the stopping of the engine and such asthe running away of the engine.

As soon as the abovesaid detector system comes into action, it causesdisengagement of the bolt 25, which permits the weight 23 to beprojected by the spring 24 against the pin 31 which then penetrates thediaphragm 17. The gas escapes from the bottle 16, expands in the nozzle33, passes through the first check-valve 19 and, by reason of thepresence of the second check-valve 21, is directed, through the portionof the delivery pipe 5 situated downstream of the point 20, towards thesupply chamber 8 of the injection pump 7 from which chamber itinstantaneously expels the fuel through the scavenging valve 10 towardsthe reservoir 2. The latter must naturally be arranged to allow thescavenging gas to escape and to prevent the fuel from being ejected tothe outside. The engine 1 is thus stopped by emptying of the injectionpump 7. In FIG. 2, there is shown in full line the normal position ofthe members 23, 25, 31, 38 and 40, that is to say before the release ofthe stop device, and in mixed line their position after release of thelatter.

When the causes of the accident have been eliminated, it suffices tofill the pipe 5 and the supply chamber 8 again, by means of a primingpump, and the engine is again ready to operate given that the gasselected is inert with respect to the liquid fuel. The stop device 13 isbesides restored into operation by substitution of the reserve bottle16a for the bottle 16 then used up and by arming the mechanism 22 bymeans of the handle 35.

The advantages of such a stop device are especially the followingcertainty of stopping and action in less than a second;

during normal operation of the engine, the gas bottle 16 beinghermetically sealed by the diaphragm 17, there is no risk ofintroduction of gas into the fuel but certainty of sound operation andespecially easy restarting of the engine 1;

the bottle 16 is always full if there is no emergency stopping;

the position of the handle 35 enables it to be easily determined whetherthe device has operated or not;

the bottles 16 which are full of gas can be easily distinguished bytheir weight from those which are empty, the weight when empty beinggenerally marked on the bottles;

the restoration into operating condition of the stop device afterfunctioning requires very little time moderate maintenance.

As is self-evident, and as emerges already from the foregoing, theinvention is in no way limited to those of its types of application, norto those of its embodiments of its various parts, which have been moreespecially indicated, it encompasses, on the contrary, allmodifications.

We claim:

1. Emergency stop device for internal combustion engines whose supplysystem includes a reservoir of liquid fuel, a primary pump having asuction pipe connected to the fuel reservoir and a delivery pipe, aninjection pump having a supply chamber in which said delivery pipeterminates and which is connected to the reservoir through a calibratedvalve (called a scavenging valve) adapted to be opened when the pressurein said chamber exceeds a predetermined threshold, and at least oneinjector receiving fuel from the injection pump to introduce it into theengine, said device comprising a hollow body which is arranged toreceive the neck of a bottle of pressurized gas, normally closed by afluid-tight diaphragm, which body has a connecting passage to a point ofsaid delivery pipe, a first checkvalve in said passage, a secondcheck-valve situated upstream of said point and a sudden actionmechanism positioned so as to pierce said diaphragm in case of accident,whereby in the portion of said delivery pipe situated downstream of saidpoint and in the supply chamber of the injection pump, there is releaseda rapid and momentary flow of said gas which displaces the fueltherefrom towards the reservoir through the scavenging valve and thuscauses stopping of the engm.

2. Stop device according to claim 1, wherein said mechanism is apercussion mechanism comprising a weight movable between an armedposition wherein it is loaded by a spring and retained by a bolt and areleased position that it can reach after liberation of said boltresulting in the piercing of the diaphragm.

3. Stop device according to claim 1, wherein it comprises the firstcheck-valve as sole element capable of opposing the flow of said gas,which enables it to cooperate with a bottle having a volumecorresponding to a single stop operation.

4. Stop device according to claim 1, wherein said gas is carbonic acidgas.

5. Stop device according to claim 1, comprising a support on which aremounted, not only the hollow body adapted to receive the bottle in useposition, but also a tubular element adapted to receive, in analogousmanner, a reserve bottle.

6. Stop device according to claim 5, wherein the support is arranged inthe form of a box shielding the essential elements of the device andprovided with openings for the passage of gas bottles.

7. Stop device according to claim 2, wherein the hollow body comprises,a first cylindrical bore in which the percussion weight is guided andhoused, a bush serving as a guide for a pin, which bush is traversed byholes enabling the gas, which comes from the bottle mounted in saidbody, to reach said point of the delivery pipe and arranged to preventthis gas from arriving at said bore and a second bore which penetratesat a right angle into the first bore and in which said bolt is guided, anozzle being adapted on the hollow body to ensure the expansion of thescavenging gas.

8. Stop device according to claim 6, wherein the weight of thepercussion mechanism is connected to an arming handle projecting outsideof the box-shaped support.

9. Device according to claim 1, wherein said mechanism is actuatedautomatically through an electromagnetic transmission or fluid underpressure, by a detector sensitive to accidents necessitating thestopping of the engine.

1. Emergency stop device for internal combustion engines whose supplysystem includes a reservoir of liquid fuel, a primary pump having asuction pipe connected to the fuel reservoir and a delivery pipe, aninjection pump having a supply chamber in which said delivery pipeterminates and which is connected to the reservoir through a calibratedvalve (called ''''a scavenging valve'''') adapted to be opened when thepressure in said chamber exceeds a predetermined threshold, and at leastone injector receiving fuel from the injection pump to introduce it intothe engine, said device comprising a hollow body which is arranged toreceive the neck of a bottle of pressurized gas, normally closed by afluid-tight diaphragm, which body has a connecting passage to a point ofsaid delivery pipe, a first check-valve in said passage, a secondcheck-valve situated upstream of said point and a sudden actionmechanism positioned so as to pierce said diaphragm in case of accident,whereby in the portion of said delivery pipe situated downstream of saidpoint and in the supply chamber of the injection pump, there is releaseda rapid and momentary flow of said gas which displaces the fueltherefrom towards the reservoir through the scavenging valve and thuscauses stopping of the engine.
 2. Stop device according to claim 1,wherein said mechanism is a percussion mechanism comprising a weightmovable between an armed position wherein it is loaded by a spring andretained by a bolt and a released position that it can reach afterliberation of said bolt resulting in the piercing of the diaphragm. 3.Stop device according to claim 1, wherein it comprises the firstcheck-valve as sole element capable of opposing the flow of said gas,which enables it to cooperate with a bottle having a volumecorresponding to a single stop operation.
 4. Stop device according toclaim 1, wherein said gas is carbonic acid gas.
 5. Stop device accordingto claim 1, comprising a support on which are mounted, not only thehollow body adapted to receive the bottle in use position, but also atubular element adapted to receive, in analogous manner, a reservebottle.
 6. Stop device according to claim 5, wherein the support isarranged in the form of a box shielding the essential elements of thedevice and provided with openings for the passage of gas bottles. 7.Stop device according to claim 2, wherein the hollow body comprises, afirst cylindrical bore in which the percussion weight is guided andhoused, a bush serving as a guide for a pin, which bush is traversed byholes enabling the gas, which comes from the bottle mounted in saidbody, to reach said point of the delivery pipe and arranged to preventthis gas from arriving at said bore and a second bore which penetratesat a right angle into the first bore and in which said bolt is guided, anozzle being adapted on the hollow body to ensure the expansion of thescavenging gas.
 8. Stop device according to claim 6, wherein the weightof the percussion mechanism is connected to an arming handle projectingoutside of the box-shaped support.
 9. Device according to claim 1,wherein said mechanism is actuated automatically through anelectromagnetic transmission or fluid under pressure, by a detectorsensitive to accidents necessitating the stopping of the engine.